The Lovers' Tryst : How I did it

The Lovers' Tryst

The Pinnacles Desert, Western Australia

This is a 40-frame panorama capturing a newly wedded couple exploring the ancient Pinnacles Desert under the pristine West-Australian night sky. It took 17 minutes to capture the entire image and a very brave couple to endure the 12 degree coastal breeze in their summer wedding dress. As a whole, the image looks complicated to capture and, to and extent, that is true. But if you break it down into a methodical workflow, capturing this image might be easier than it seems. 

 

Capturing the Image

This image started to take shape when a mate of mine, Ashley Lam, asked me to be the photographer for his wedding. He asked that I not only document the wedding, but also do an Astro-Wedding shot for their wedding photo at a later time. I couldn't say no to the request and started thinking about some locations and compositions. Having traveled along the western coast of Australia quite a bit, I picked out two suitable locations in consideration of the logistics of the shoot. We had to take into account that we had to be in a suitably dark location (typically 1.5 - 2 hrs out of the city), and that both the bride and groom would be wearing their wedding attires which could possibly hinder movement, thus ruling out uneven terrain. I ended picking either the Lancelin Sand Dunes or the Pinnacles Desert, both around 2 hrs North of Perth, both with easy access using any vehicle. The couple decided on the Pinnacles. 

As the Milky Way season starts to peak from the month of May, the core rises earlier on in the night and reaches my desired elevation for the composition at around 9:30pm. The couple arrived at the location at 8pm to do some practice and test shots. I got them to stand in the right pose and angled both their bodies 45 degrees to the left with their backs towards the camera. Put their weight on their left leg and slightly lean forward, and point the heal of their right foot towards the sky. Tilt their heads upwards and stretch their arms out at 45 degrees. This would give an illusion that they are "leaning into the picture". The groom would be tasked with holding the light. We practiced holding the pose for a while until it was time to shoot. 

When the Milky Way had reached the right elevation, I lead them to a spot I had picked out before they arrived and asked them to stand there while I set up my camera equipment. 

For this shoot, I used a Nikon D750 DSLR equipped with an Optolong L-Pro light pollution filter and Nikon 20mm f1.8G lens. For the camera support, I used a Gigapan Epic Pro panorama mount and a Monoprice Carbon Fiber tripod. Using this set up, it would take 17 minutes to capture an entire photosphere with a 20 second exposure and a 40% overlap between the 40 frames in an 5 row by 8 column grid pattern. 

I also used a Yong Nuo 565EX speedlight equipped with a Gary Fong Lightsphere and Yong Nuo RF603N ii Wireless transmitters for the wireless lighting.  

Shot settings used were ISO 3200, F2.2 and 20 seconds shutter speed. 

Equipment

Nikon D750 FX DSLR

Optolong L-Pro Light Pollution Filter

Gigapan Epic Pro Robotic Panorama Mount

Yong Nuo 565EX + Gary Fong Lightsphere

For the first half the shot, the camera was capturing the sky and the couple were free to soak in the view of the Milky Way. After 8 minutes, I asked them to get ready and I turned on the wireless transmitters to trigger the flash to illuminate the scene. For the next 2 exposures, the groom had to lift the speedlight up at the start of the exposure before it fires and then relax his arm again. This was so he could keep up his strength before needing to hold the pose properly. After the 2 frames, I ran towards them and collected their jackets and other insulation clothing and told them to hold the pose for the next 3 frames which they would appear in. I ran back to the camera and continued to shoot. Once those 3 frames were completed, I handed them their jackets back, by which time they were feeling pretty damn cold. The couple still had to stand in position while the camera captured the rest of the foreground while the groom lifted the speedlight up at the start of every exposure to keep the shadows consistent between frames. 

All in all, the couple stood totally still for about 65 seconds out of the 17 minutes. 

We shot another 2 panoramas before calling it a night at about 11pm, and then a 2 and a half hour drive home. Being quite an experienced when it comes to driving on the coastal road at night, I took point and lead the couple back towards the city, lighting up the way with a 9000 Lumen driving light ( I counted 7 kangeroos and 1 owl on the drive home that night).

 

RAW File Preparation

Upon returning home at about 1:30am, I downloaded the RAW files off my SD card and loaded them up into Adobe Lightroom for inspection and preparation. I have done astrophotography sessions at the Pinnacles multiple times before but never with a light pollution filter. I used the Optolong L-Pro filter for this shoot and wanted to see the effects of the filter.

L-Pro Summary

What I like:

- The L-Pro filter sits inside the mirror chamber, out of the way and filters the already corrected light that has passed through the lens instead of being filtered before corrected in a traditional screw mount filter.

- It's sharp. There is no perceivable difference in sharpness when using the L-Pro compared to not using it.

- It works as described. The filter works by attenuating the undesirable parts of the light spectrum emitted by sodium vapour lights. It also increases the contrast of the Milky Way and other celestial objects, bringing out the vivid colours of night sky.

- It's not limited to a single lens thread size as it sits inside the camera. 

What I dislike:

- You lose about 2/3 stops of light and have to compensate with a larger aperture or longer shutter speed. 

- Clumsy installation. It's not that bad once you're used to installing and removing the filter, but my initial attempts to install it were quite frustrating having not known the correct technique to install it. Once I figured it out, installing it became a 20 second job. 

- Flaring issues. I'm not sure if it's just because of the speedlight I used, but I did notice several green flare marks in the RAW files which I've never seen before using the D750 and 20mm 1.8G combo before. I suspect that the flaring comes from internal reflections in the mirror chamber. 

Initial inspection of the RAW files showed that they were sharp and in focus. The Milky Way looked good straight out of camera and the lighting between the foreground frames looked consistent enough to stitch. I did my pre-stitch RAW file preparation in Lightroom which included adjusting:

- Colour Profile: Change from Adobe Colour to Camera Neutral

- Lens Correction: Remove Chromatic Aberration and Enable Lens Profile Correction

- Adjust White Balance

- Basic Adjustments: White and Black sliders

- Add Clarity, Vibrance and Saturation

- 'S' curve applied to the Tone Curve

With these adjustments made, the RAW files were exported as 16bit TIFF files, ready to be stitched. Each TIFF file came up to 120mb. All 40 frames together came up to 4.8Gb worth of data.

Stitching

Once the RAW files had been exported as TIFF files, the images were imported to Autopano Giga, my stitch software of choice. Using the Gigapan plugin, I synced the shoot layout and overlap amount within Autopano Giga to aide in the stitching process. Selecting the right settings in Autopano will relieve some stress on the stitching algorithm which will result in a more efficient workflow. 

After the TIFF files are stitched together, you get an initial projection of what the final image would look like. Being a 360 photosphere, we have the opportunity to decide what type of projections type we would like to use and we also have the ability to mildly recompose the shot after the fact. For ultra-wide angle panoramas, I prefer to use a "Stereographic" projection which maintains straight lines and is able to project around 270 degrees without major distortion. There are also other projection types like Spherical, Mercator and Little World. Each of these projection types have their uses, but the case of an ultra-wide panorama, Stereographic projections work best. I re-position the image to get the desired composition and crop it down to a usable aspect ratio.  

Because of the way the frames are overlapped, that couple will appear in multiple frames. I want to force Autopano to use the image of the couple posing from one particular frame where they are holding the pose the best, while masking them out in the other frames they appear in. This will ensure that no stitch errors will occur at the most critical part of the final image.

I render out the stitched image as a 16bit TIFF file. The final megapixel count is above 220MP for this image. The megapixel count will depend greatly on the focal length and sensor pixel density. The stitched image is then imported into Lightroom for processing. 

 

Processing the Final Image

I generally process my milky way photos to taste rather than scientific accuracy. I prefer a high-contrast dramatic look and this can be achieved be finely adjusting the Tone-Curve and using Graduated Filters. As for the colour balance, I prefer a neutral look leaning slightly towards magenta. 

Understanding the capabilities of your camera sensor is advantageous when it comes to editing the files it produces. Some camera sensors have more dynamic range than others while some have less colour noise and grain. These factors will limit the amount of processing the stitched file could take before breaking or become visually unacceptable. The D750 is a near ISO invariant camera which allows the ISO to be raised after the image is captured by lifting the exposure in post production. This allows me to capture more highlight data while selectively raising the shadow areas to keep noise to a minimum. As such, the sky of this image is essentially at ISO3200 while the foreground is closer to ISO8000. I tend to use heavy vignettes as well to add to the dramatic look. 

Once I am satisfied with the Lightroom edit, the image is then imported into Photoshop for some finishing touches such as removing any unwanted artifacts like lens flare and minor stitch marks, and applying a "Bloom" effect, a contrast-enhancing editing technique inspired from character model lighting in video games (more on this topic in a future article). 

 

Final Thoughts

The process of capturing a wide field panorama of the night sky can be lengthy and tiresome, but extremely rewarding. The reality is that Nightscape Astrophotography is a very challenging genre of photography and requires a lot of planning, research, study and a hell lot of luck. 

Overall, I am quite pleased with the results of this shoot. It's great to see the final image take shape after having the composition in my head for so long. It's definitely one of my more memorable astrophotography adventures. 

 

How to : PANORAMAS : 360 Photospheres

Pinnacles of Adventure Photosphere

Pinnacles Desert, Western Australia


Good day. Over the past few months, I've been driving around to some iconic locations along the West Australian coast at night to capture 360 degree photospheres, showing the beauty of dark skies above the Australian landscape. 

I've found that photospheres are an effective way to enable the viewer to experience what it is like to be there for themselves. Coupled up with a VR headset, photospheres are truly an immersive way of experiencing Astrophotography.

In this post, I'll be writing on how I prepare, stitch and project my 360 photospheres. The image that we will be working on consists of 80 individual images shot in a 10 x 8 grid in landscape orientation with each image being overlapped by 50%. 

The most important thing to remember in photospheres is to shoot a full 360 degree by 180 degree to ensure a 2 x 1 aspect ratio for the final image.

It was shot using a Nikon D750 DSLR, Sigma 24mm ART lens and a Gigapan Epic Pro panorama mount. Total shooting time was around 40 minutes.

Settings:

ISO 3200

F1.8

25 seconds x 80 frames

Here's the layout of how the images were shot.


Preparing the RAW files

Before we stitch and project our images, we need to prepare the RAW files by correcting the White Balance, Lens Distortion, Lens Coma, Lens Vignetting and add some Noise Reduction. These steps will help us a lot in the stitching process by removing any image artifacts which puts less stress on the stitching software.

First import all the images to Lightroom and click on the "Develop" module to process the images. 

Once in we're in the Develop Module, we can start with the Lens corrections. I tend to work on a single image that contains the Milky Way core to get an accurate White Balance. We generally want the core to be pale yellow in colour. 

Let's remove the vignetting and lens distortion by enabling the Profile Corrections. Ensure that the "Remove Chromatic Aberrations" box is checked as well.

Now that we have a flat and evenly exposed image, we will go ahead with the White Balancing. The way we do this is to slide the "Vibrance" and "Saturation" sliders to +100 to have a look at what colours data was captured in the image. 

As you can see, we have far too much blue and magenta in the SOOC shot. We generally want the core of the Milky Way to be pale yellow and the rest of the sky to be a good mixture of green and magenta. 

Slide the Temp and Tint sliders until we achieve the desired White Balance. 

Once we are satisfied with the White Balance, we can reset the Vibrance and Saturation sliders back to 0. 

The next thing we need to do is a minor technical clean up by removing the default sharpening that Lightroom applies to all images and add some minor noise reduction.

Our image is now ready to by stitched, we just need to sync the settings to the rest of the images and export them in the correct format. 

Finally, we can export our images with the following settings: (Note that I downsize my images from 24mp to 12mp to save on storage space)


Stitching and Projection

My preferred stitching software is Autopano Giga. However, Microsoft ICE will do the job as well. 

If you need a detailed guide on how to stitch images in Autopano Giga, I've written one here.

Ensure the image is projected as a Spherical projection.

The spherical projection is a 2D representation of a 3D sphere. The distortion towards the top and bottom of the image is a result of this projection, not lens coma or aberrations, and is perfectly normal. 

Render the image as a 16bit TIFF file.


Lightroom Processing and Export

Import the stitched image into Lightroom for processing. Ensure the final image is in 2 x 1 aspect ratio or the image will not be projected as a sphere.

Finally! We can export our photosphere. Export the image as a JPEG at 300dpi and ensure that the long side of the image is no wider than 12000 pixels. This is because Google Street View doesn't allow images wider than 12000 pixels.

If you want to upload your image to Facebook, this limitation does not exist.


Upload to Facebook or Google Street View

And we're done! Upload the exported image to Facebook or Google Street View and it will automatically recognize it as a 360 Photosphere!

If you found this article helpful, give us a like on our facebook page and leave us a comment!

How to : PANORAMAS : Stitching

Have you ever felt that a 14mm F2.8 Rectilinear lens on a Full Frame DSLR just wasn't wide enough?

Have you ever wanted to shoot wider than the field of view of your lens?

You can... with a 24mm.

 

Welcome to ASTRORDINARY Imaging. My name is Paean Ng, a self-taught astrophotographer based in Perth, Western Australia.

I've recently been asked by several people to write tutorials on how I produce my images. So here's the first tutorial in a new "How to" series.

I've been using the Sigma 24mm F1.4 ART lens along with a Nikon D750 as my main shooting combo for the past year and have come to know this particular set up intimately. Along with my Gigapan Epic Pro, this is the main set up I use to shoot panoramas and photospheres.

People prefer different looks to their photos. Some like the standard 50mm perspective and some like the ultra-wide and distorted perspective. It's important to know, however, that the perspective of the resulting panorama will be the same as the perspective of the lens it was shot on. In other words, stitching multiple images shot on a 24mm will NOT result in an image that looks like a 14mm. It will just look like a very wide 24mm perspective. 

With that being said, I like the 24mm perspective because it's the widest angle in the standard 24-70 field of view. 

Lets jump right in. I'll be basing this tutorial on a panorama I shot at Sugarloaf Rock, Dunsborough.

This is the equipment and settings that were used. 

Equipment:

Nikon D750

Sigma 24mm ART

Gigapan Epic Pro

Shooting Settings:

ISO 3200

F2.0

20 seconds

35 frames. (7x5 grid in landscape orientation)

Before the stitching process begins, I first prepare the images by importing them into Lightroom and applying the appropriate Lens Correction Profiles and roughly change the White Balance of the image. Sync the changes throughout all the images and export them as 16bit TIFF files.

My preferred stitching software is Autopano Giga. It's extremely powerful and really simple to use, but it does cost. A free alternative is Microsoft ICE. You won't have all the functionality of a paid product, but it works. 

 

Import the prepared images into Autopano Giga and click "Settings", which is the Spanner icon next to "Detect". 

 

These are the settings I use. I find that keeping the "Detection" on automatic works best.

 

Ensure all colour corrections options have been turned off. 

 

Once all the settings are correct, go ahead and click the "Detect" button and let Autopano Giga do it's thing. Once the initial detection is done, you will be see something like this:

Double click on the projected image on the right to bring up the Edit screen. If the image looks distorted, split, incomplete or anything else that might get you worried, relax, its normal. We'll fix it.

 

Use the "Move" tool to reposition the image until it is centered.

 

By default, Autopano Giga will project the image as a Spherical projection. You can change the way the panorama is projected by changing the Projection Settings:

The Projection I use most is "Little Planet" with a locked Horizon. This style of projection is the same as a Stereographic projection in Microsoft ICE and PTGui. Play around with the different projections and you might find something you like. 

Now we need to resize the projection by sliding the "Squeeze" button up to around 0.35 and crop out the unwanted parts. 

Now we have a working image, scaled to the correct size and roughly cropped to what we want. If the panorama was shot correctly, you shoudn't run into any stitch errors. If you do have errors, however, they can be fixed by manually adding control points by clicking on the "Control Point" button.

If you find a stitch error in the sky, don't bother correcting it. There are thousands of stars in each frame, I doubt a minor stitch error is going to make a difference to that.

Once you're satisfied, render the image with the following settings and then import it to Lightroom.

Ensure the image is rendered as a TIFF file at 16bits, 300dpi to maintain all the RAW goodness for processing in Lightroom.

Final Edit.

 

There we go, that's the way I stitch my panoramas. I hope this guide was useful. Please leave a comment and follow me on facebook. www.facebook.com/astrordinary

 

 

Paean Ng